What’s wrong with my tomatoes? | NevadaAppeal.com

What’s wrong with my tomatoes?

JoAnne Skelly
For the Appeal

Nothing tastes better than home-grown tomatoes! To have delicious tomatoes can be the reason many of us have a vegetable garden in the first place. We start plants indoors, nurturing the seedlings until planting time.

We carefully prepare our soil, putting in all the amendments that will help our plants grow. We protect them from the cold. We water and feed. We train them on cages and we prune them to increase yield. All this effort should bring us beautiful fruit.

But, what happens?

Tomatoes grow that are blackened on the bottom. Or the tops can be cracked.

Blackened bottoms are “blossom-end rot.” Blossom-end rot is aggravated by changes in soil moisture from dry to wet, rapid growth early in the season followed by extended dry weather, excessive rains or high soil salt content. This condition of tomatoes is more common on sandy soils.

Cultivating too close to the plant can damage roots and reduce the ability of the plant to absorb water. High temperatures and winds can make it difficult for plants to absorb water quickly enough to meet their needs.

Place mulch around the plants to keep them evenly moist. Do not hoe deeper than 1 inch within one foot of a plant to avoid root damage. Maintain even soil moisture, neither water-logging a plant, not letting it dry out too much.

Blossom-end rot can also happen to peppers, squash and watermelons. Some vegetable varieties are more susceptible than others.

If you had a problem with blackened bottoms this year, buy a different variety next year. If you have a sandy soil, add humus or compost to it in the fall and spring to build up its water-holding capacity.

Concentric rings of cracking around a stem on tomatoes may be due to rapid growth after a heavy rainfall followed by a dry spell.

Temperatures above 90 degrees Fahrenheit and intense sunlight can cause large radiating cracks from the stem. A way to avoid tomato cracking is to remove the fruit immediately after a rain.

Keeping the soil evenly moist and maintaining good leaf cover can reduce radiating cracking. Try to select varieties and planting times that will allow the fruit to develop when temperatures are less than 90 degrees.

For more information, e-mail skellyj@unce.unr.edu or call me at 887-2252. You can “Ask a Master Gardener” by e-mailing mastergardeners@unce.unr.edu or call your local University of Nevada Cooperative Extension office. Check out many useful horticulture publications at http://www.unce.unr.edu.

– JoAnne Skelly is the Carson City/Storey County Extension educator for University of Nevada Cooperative Extension.